How To Use iMovie to Edit Clips
Step one: Opening iMovie
(if you already have iMovie open and your clips ready, you can skip this step)

First you need to open iMovie. Hopefully you have already downloaded your video clips. If not, you need to do that. Refer to How to Use iMovie to import video from a digital video camera to complete these steps.

Once iMovie opens, you need to locate your file on the LaCie Hard Drive or on the Desktop. Open the file. It should open at the edit screen with your clips in the right hand column. 
iMovie Opening Screen
Step two: The Main Screen

When iMovie opens, you should have a screen similar to the one at the right. The number of clips on the right side will depend upon the number of clips you downloaded. You can clip on each individual clip and play it to preview your clips. Clips will be played in the big black screen to the left. 
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Step three: Changing Views

There are two ways to view your project: clip viewer or timeline viewer. To toggle between the two views, you need to locate the button located below.
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If you click on the picture of the film (left), you will be using the clip viewer.
If you click on the picture of the clock (right), you will be using the timeline viewer.

You can edit your footage using either viewer mode. 
This menu bar is located at the bottom of the screen. To toggle between viewers, click the button on the far left.
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Step four: Drag Down your Clips

Once you have determined which clip you would like to edit, you need to drag it to the viewer. To do this, click on the clip until the top and bottom section are blue. Keep holding down on the mouse button and drag the clip to the viewer.

Release the mouse button once the clip has reached the viewer.

You can add multiple clips at a time or drag each clip down as it is needed during your project.
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Step five: Splitting Your Clips

As you view your clips, you may find pieces that you do not want included in your project. You need to remove these portions by splitting your clip and removing the unwanted part. This process is best done in the timeline viewer.

When you find the portion you want to move or separate, pause the clip by pressing the play button.

Then find Edit on the main iMovie menu bar. When the menu drops down, click on Split Video Clip at Playhead. For each section that needs to be cut, repeat this process.

You can delete the unwanted portion or you can drag it back to where the other clips are (top right) and drop it in an empty box.
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Splitting a Clip

When splitting clips make sure you leave a few seconds lead time on the beginning and end of each section especially if you plan on using a transition. You can always do a final trim before you finish your project.
NOTE: If you need to make a very precise edit, you can advance the clip frame by frame using the marker circled below. Simply drag the marker slowly to the left or right and it will help you find the exact spot. For this reason, it is easier to edit clips in the timeline viewer.
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